diff --git a/application/src/Entity/Source/Attribut/GroupSourcesAttribut.php b/application/src/Entity/Attribut/GroupSourcesAttribut.php
similarity index 93%
rename from application/src/Entity/Source/Attribut/GroupSourcesAttribut.php
rename to application/src/Entity/Attribut/GroupSourcesAttribut.php
index cf61781..a38ab8a 100644
--- a/application/src/Entity/Source/Attribut/GroupSourcesAttribut.php
+++ b/application/src/Entity/Attribut/GroupSourcesAttribut.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace App\Entity\Source\Attribut;
+namespace App\Entity\Attribut;
 
 use Doctrine\Common\Collections\Collection;
 use App\Entity\Source\GroupSourceInterface;
diff --git a/application/src/Entity/Source/Attribut/GroupSourcesAttributInterface.php b/application/src/Entity/Attribut/GroupSourcesAttributInterface.php
similarity index 91%
rename from application/src/Entity/Source/Attribut/GroupSourcesAttributInterface.php
rename to application/src/Entity/Attribut/GroupSourcesAttributInterface.php
index 61ead32..8a5cfd1 100644
--- a/application/src/Entity/Source/Attribut/GroupSourcesAttributInterface.php
+++ b/application/src/Entity/Attribut/GroupSourcesAttributInterface.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace App\Entity\Source\Attribut;
+namespace App\Entity\Attribut;
 
 use Doctrine\Common\Collections\Collection;
 use App\Entity\Source\GroupSourceInterface;
diff --git a/application/src/Entity/Attribut/SourceCollectionAttribut.php b/application/src/Entity/Attribut/SourceCollectionAttribut.php
new file mode 100644
index 0000000..d7c2035
--- /dev/null
+++ b/application/src/Entity/Attribut/SourceCollectionAttribut.php
@@ -0,0 +1,23 @@
+<?php
+namespace App\Entity\Attribut;
+
+use Doctrine\Common\Collections\Collection;
+use App\Entity\Source\SourceInterface;
+
+trait SourceCollectionAttribut
+{
+    /**
+     * @param Collection|SourceInterface[] $collection
+     */
+    public function setCollection(Collection $collection):void{
+        
+    }
+    
+    /**
+     * @return Collection|SourceInterface[]
+     */
+    public function getCollection():Collection{
+        
+    }
+}
+
diff --git a/application/src/Entity/Attribut/SourceCollectionAttributInterface.php b/application/src/Entity/Attribut/SourceCollectionAttributInterface.php
new file mode 100644
index 0000000..6dcc8e3
--- /dev/null
+++ b/application/src/Entity/Attribut/SourceCollectionAttributInterface.php
@@ -0,0 +1,18 @@
+<?php
+namespace App\Entity\Attribut;
+
+use Doctrine\Common\Collections\Collection;
+use App\Entity\Source\SourceInterface;
+
+interface SourceCollectionAttributInterface
+{
+    /**
+     * @param Collection|SourceInterface[] $collection
+     */
+    public function setCollection(Collection $collection):void;
+    
+    /**
+     * @return Collection|SourceInterface[]
+     */
+    public function getCollection():Collection;
+}
\ No newline at end of file
diff --git a/application/src/Entity/Source/AbstractSource.php b/application/src/Entity/Source/AbstractSource.php
index 1dbb55a..5cf1ac4 100644
--- a/application/src/Entity/Source/AbstractSource.php
+++ b/application/src/Entity/Source/AbstractSource.php
@@ -6,7 +6,7 @@ use Doctrine\ORM\Mapping as ORM;
 use JMS\Serializer\Annotation\Exclude;
 use App\Entity\AbstractEntity;
 use Doctrine\Common\Collections\Collection;
-use App\Entity\Source\Attribut\GroupSourcesAttribut;
+use App\Entity\Attribut\GroupSourcesAttribut;
 use App\Entity\Meta\RelationInterface;
 use App\Entity\Attribut\RelationAttribut;
 use App\Entity\Meta\Relation;
@@ -14,6 +14,7 @@ use App\Entity\Attribut\LawAttribut;
 use App\Entity\Meta\LawInterface;
 use App\Entity\Meta\Law;
 use Doctrine\Common\Collections\ArrayCollection;
+use App\Entity\Source\Collection\MemberCollectionSource;
 
 /**
  * @author kevinfrantz
@@ -41,7 +42,7 @@ abstract class AbstractSource extends AbstractEntity implements SourceInterface
      * @todo Implement that just one table on database level is needed!
      * @todo Rename table to use the right schema
      *
-     * @var Collection|GroupSource[]
+     * @var Collection|MemberCollectionSource[]
      * @ORM\ManyToMany(targetEntity="GroupSource",mappedBy="members")
      */
     protected $groups;
diff --git a/application/src/Entity/Source/Collection/AbstractCollectionSource.php b/application/src/Entity/Source/Collection/AbstractCollectionSource.php
new file mode 100644
index 0000000..d314ed2
--- /dev/null
+++ b/application/src/Entity/Source/Collection/AbstractCollectionSource.php
@@ -0,0 +1,9 @@
+<?php
+namespace App\Entity\Source\Collection;
+
+use App\Entity\Source\AbstractSource;
+
+class AbstractCollectionSource extends AbstractSource implements CollectionSourceInterface
+{
+}
+
diff --git a/application/src/Entity/Source/Collection/CollectionSourceInterface.php b/application/src/Entity/Source/Collection/CollectionSourceInterface.php
new file mode 100644
index 0000000..c83520b
--- /dev/null
+++ b/application/src/Entity/Source/Collection/CollectionSourceInterface.php
@@ -0,0 +1,8 @@
+<?php
+namespace App\Entity\Source\Collection;
+
+use App\Entity\Source\SourceInterface;
+
+interface CollectionSourceInterface extends SourceInterface
+{}
+
diff --git a/application/src/Entity/Source/GroupSource.php b/application/src/Entity/Source/Collection/MemberCollectionSource.php
similarity index 78%
rename from application/src/Entity/Source/GroupSource.php
rename to application/src/Entity/Source/Collection/MemberCollectionSource.php
index a25369f..0012ebf 100644
--- a/application/src/Entity/Source/GroupSource.php
+++ b/application/src/Entity/Source/Collection/MemberCollectionSource.php
@@ -1,19 +1,17 @@
 <?php
 
-namespace App\Entity\Source;
+namespace App\Entity\Source\Collection;
 
 use Doctrine\ORM\Mapping as ORM;
 use Doctrine\Common\Collections\Collection;
-use App\Entity\Attribut\MembersAttributInterface;
 use App\Entity\Attribut\MembersAttribut;
 use Doctrine\Common\Collections\ArrayCollection;
-
 /**
  * @author kevinfrantz
  * @ORM\Table(name="source_group")
  * @ORM\Entity
  */
-final class GroupSource extends AbstractSource implements MembersAttributInterface
+final class MemberCollectionSource extends AbstractCollectionSource implements MemberCollectionSourceInterface
 {
     use MembersAttribut;
 
diff --git a/application/src/Entity/Source/Collection/MemberCollectionSourceInterface.php b/application/src/Entity/Source/Collection/MemberCollectionSourceInterface.php
new file mode 100644
index 0000000..148a687
--- /dev/null
+++ b/application/src/Entity/Source/Collection/MemberCollectionSourceInterface.php
@@ -0,0 +1,12 @@
+<?php
+
+namespace App\Entity\Source\Collection;
+
+use App\Entity\Attribut\MembersAttributInterface;
+
+/**
+ * @author kevinfrantz
+ */
+interface MemberCollectionSourceInterface extends MembersAttributInterface,CollectionSourceInterface
+{
+}
\ No newline at end of file
diff --git a/application/src/Entity/Source/Collection/Queue/QueueSourceInterface.php b/application/src/Entity/Source/Collection/Queue/QueueSourceInterface.php
new file mode 100644
index 0000000..792ae92
--- /dev/null
+++ b/application/src/Entity/Source/Collection/Queue/QueueSourceInterface.php
@@ -0,0 +1,17 @@
+<?php
+namespace App\Entity\Source\Collection\Queue;
+
+use App\Entity\Attribut\MembersAttributInterface;
+use App\Entity\Source\Collection\CollectionSourceInterface;
+use App\Entity\Source\SourceInterface;
+
+/**
+ * @todo Implement integration test for two user accessing queue! Check if log works!
+ * @author kevinfrantz
+ */
+interface QueueSourceInterface extends CollectionSourceInterface, MembersAttributInterface
+{
+    public function getPointerPosition():int;
+    
+    public function getNextElement():SourceInterface;
+}
\ No newline at end of file
diff --git a/application/src/Entity/Source/GroupSourceInterface.php b/application/src/Entity/Source/GroupSourceInterface.php
deleted file mode 100644
index 167d3cb..0000000
--- a/application/src/Entity/Source/GroupSourceInterface.php
+++ /dev/null
@@ -1,14 +0,0 @@
-<?php
-
-namespace App\Entity\Source;
-
-use App\Entity\Attribut\MembersAttributInterface;
-
-/**
- * @author kevinfrantz
- *
- * @todo Map the not jet mapped functions!
- */
-interface GroupSourceInterface extends MembersAttributInterface
-{
-}
diff --git a/application/src/Entity/Source/SourceInterface.php b/application/src/Entity/Source/SourceInterface.php
index bb49ca9..93f1514 100644
--- a/application/src/Entity/Source/SourceInterface.php
+++ b/application/src/Entity/Source/SourceInterface.php
@@ -4,7 +4,7 @@ namespace App\Entity\Source;
 
 use App\Entity\Attribut\IdAttributInterface;
 use App\Entity\EntityInterface;
-use App\Entity\Source\Attribut\GroupSourcesAttributInterface;
+use App\Entity\Attribut\GroupSourcesAttributInterface;
 use App\Entity\Attribut\LawAttributInterface;
 use App\Entity\Attribut\RelationAttributInterface;
 
diff --git a/application/tests/Unit/Entity/Attribut/MembersAttributTest.php b/application/tests/Unit/Entity/Attribut/MembersAttributTest.php
index e8ca2b2..07cad40 100644
--- a/application/tests/Unit/Entity/Attribut/MembersAttributTest.php
+++ b/application/tests/Unit/Entity/Attribut/MembersAttributTest.php
@@ -6,7 +6,6 @@ use App\Entity\Attribut\MembersAttribut;
 use App\Entity\Attribut\MembersAttributInterface;
 use Doctrine\Common\Collections\ArrayCollection;
 use App\Entity\Source\AbstractSource;
-use App\Entity\Source\GroupSource;
 use App\Tests\AbstractTestCase;
 
 class MembersAttributTest extends AbstractTestCase
@@ -18,7 +17,11 @@ class MembersAttributTest extends AbstractTestCase
 
     public function setUp(): void
     {
-        $this->membersAttribut = new class() implements MembersAttributInterface {
+        $this->membersAttribut = $this->getMembersAttributClassMock();
+    }
+    
+    private function getMembersAttributClassMock():MembersAttributInterface{
+        return new class implements MembersAttributInterface{
             use MembersAttribut;
         };
     }
@@ -62,7 +65,7 @@ class MembersAttributTest extends AbstractTestCase
 
     public function testFirstLevelMembersInclusiveChildren(): void
     {
-        $source1 = new GroupSource();
+        $source1 = $this->getMembersAttributClassMock();
         $source2 = clone $source1;
         $source3 = clone $source1;
         $source4 = clone $source1;
@@ -74,13 +77,14 @@ class MembersAttributTest extends AbstractTestCase
 
     public function test3DimensionsMembersInclusiveChildren(): void
     {
-        $source1 = new GroupSource();
+        $source1 = $this->getMembersAttributClassMock();
         $source2 = clone $source1;
         $source3 = clone $source1;
         $source4 = clone $source1;
         $source1->setMembers(new ArrayCollection([$source2]));
         $source2->setMembers(new ArrayCollection([$source3]));
         $source3->setMembers(new ArrayCollection([$source4]));
+        $source4->setMembers(new ArrayCollection());
         $this->membersAttribut->setMembers(new ArrayCollection([$source1]));
         $this->assertEquals(1, $this->membersAttribut->getMembers()->count());
         $this->assertEquals(1, $source1->getMembers()->count());
@@ -92,7 +96,8 @@ class MembersAttributTest extends AbstractTestCase
 
     public function testMembersIncludingChildrenInfinite(): void
     {
-        $source1 = new GroupSource();
+        $source1 = $this->getMembersAttributClassMock();
+        $source1->setMembers(new ArrayCollection());
         $source2 = clone $source1;
         $source3 = clone $source1;
         $source4 = clone $source1;
diff --git a/application/tests/Unit/Entity/Source/Collection/MemberCollectionSourceTest.php b/application/tests/Unit/Entity/Source/Collection/MemberCollectionSourceTest.php
new file mode 100644
index 0000000..fe567ae
--- /dev/null
+++ b/application/tests/Unit/Entity/Source/Collection/MemberCollectionSourceTest.php
@@ -0,0 +1,43 @@
+<?php
+namespace Tests\Unit\Entity\Source\Collection;
+
+use PHPUnit\Framework\TestCase;
+use Doctrine\Common\Collections\Collection;
+use Doctrine\Common\Collections\ArrayCollection;
+use App\Entity\Source\AbstractSource;
+use App\Entity\Source\Collection\MemberCollectionSourceInterface;
+use App\Entity\Source\Collection\MemberCollectionSource;
+
+/**
+ *
+ * @author kevinfrantz
+ */
+class MemberCollectionSourceTest extends TestCase
+{
+
+    /**
+     *
+     * @var MemberCollectionSourceInterface
+     */
+    protected $groupSource;
+
+    public function setUp(): void
+    {
+        $this->groupSource = new MemberCollectionSource();
+    }
+
+    public function testConstructor(): void
+    {
+        $this->assertInstanceOf(Collection::class, $this->groupSource->getMembers());
+    }
+
+    public function testMembers()
+    {
+        $member = new class() extends AbstractSource {};
+        $this->groupSource->setMembers(new ArrayCollection([
+            $member
+        ]));
+        $this->assertEquals($member, $this->groupSource->getMembers()
+            ->get(0));
+    }
+}
diff --git a/application/tests/Unit/Entity/Source/GroupSourceTest.php b/application/tests/Unit/Entity/Source/GroupSourceTest.php
deleted file mode 100644
index d78fa29..0000000
--- a/application/tests/Unit/Entity/Source/GroupSourceTest.php
+++ /dev/null
@@ -1,35 +0,0 @@
-<?php
-
-namespace tests\unit\Entity\Source;
-
-use App\Entity\Source\GroupSourceInterface;
-use App\Entity\Source\GroupSource;
-use PHPUnit\Framework\TestCase;
-use Doctrine\Common\Collections\Collection;
-use Doctrine\Common\Collections\ArrayCollection;
-use App\Entity\Source\AbstractSource;
-
-/**
- * @author kevinfrantz
- */
-class GroupSourceTest extends TestCase
-{
-    /**
-     * @var GroupSourceInterface
-     */
-    protected $groupSource;
-
-    public function setUp(): void
-    {
-        $this->groupSource = new GroupSource();
-    }
-
-    public function testMembers()
-    {
-        $this->assertInstanceOf(Collection::class, $this->groupSource->getMembers());
-        $member = new class() extends AbstractSource {
-        };
-        $this->groupSource->setMembers(new ArrayCollection([$member]));
-        $this->assertEquals($member, $this->groupSource->getMembers()->get(0));
-    }
-}